How and Why Cats Purr

By Susan McCullough

Did you know that, like vibrating piano strings, the sounds and vibrations your purring cat emits are in perfect musical harmony with each other? Those positive vibrations form the basis of one of the most soothing and pleasurable means of communication in the entire animal kingdom. Usually, your cat is telling you, “I’m feeling good.”

In addition to the messages purring can send to you and others, it offers physical benefits to both felines and the lucky people petting them.

Purring MechanicsDespite all of our high-tech advancements, the anatomical and mechanical roots of your cat’s purr aren’t entirely known. “Theories are that it is a vibration of the larynx [voice box] or diaphragm,” says Elaine Wexler-Mitchell, DVM, author of Ask the Vet about Cats (BowTie Press 2004). “The vibration is stimulated by neural messages sent from the brain.”

Cat behavior expert Amy Shojai, author of PETiquette: Solving Problems in Your Multi-Cat Household (M. Evans 2005), says that purring results when laryngeal muscles alternately open and close the glottis [the combination of the vocal chords and the space between the folds], causing a sudden separation of the vocal chords. The sound is due to the sudden buildup and release of pressure from the inhaling and exhaling of breath.

Purring MessagesEven though your cat purrs the same way no matter what’s going on, the circumstances surrounding the purring determine what your pet is communicating. Often it’s contentment -- a reflection of your cat’s perception that all is right in its world. However, those feline rumbles may be sending a different message in some situations. These messages include:

“I’m a nice kitty” Some cats may purr to signal to other cats that they’re friendly and want to come closer to them. In certain situations, a cat purrs to signal to another party -- feline or human -- that it poses no threat to that individual. If your cat purrs while being handled at the vet and also head bumps with forward-facing ears, she’s probably signaling that she poses no threat and feels minimal fear.

“I want to reassure myself” A cat that’s feeling nervous or upset may respond by purring. “Cats that are gravely ill will purr,” notes Wexler-Mitchell. “Purring in this situation may provide some comfort.” Dying cats are also known to purr, as are cats giving birth.

“I’m OK, you’re OK” Many experts believe that kittens, which can purr when they are only 2 days old, do so to signal to their mothers that everything is fine. The mother not only hears the sound of the kitten’s purring but also feels the vibration. Mother cats are likely to purr back to their offspring in the same spirit of reassurance.

Physical BenefitsWhile mother cats and kittens use purring to let each other know that everything’s all right, purring also helps ensure the kittens’ survival. That’s because newborn kittens, like many newborn animals, can’t see or hear. However, they can feel the vibrations of their mother’s purring, and those vibrations can guide them to their mother and enable them to nurse. The kittens then continue to purr while they nurse, as the vibrations reassure the mother cat that her babies are where they’re supposed to be and doing what they’re supposed to be doing.

Researchers have additionally found that purring may have healing properties too. “Interesting studies indicate that purrs help speed healing, particularly of broken bones,” notes Shojai. Scientists have also found that low-level vibrations, such as those in feline purring, may help strengthen bones as well as muscles, ligaments and tendons -- which may account for the relative rarity of muscle and bone diseases in cats.

Finally, purring has a calming effect. Because of this quality, cats often serve as therapy animals in health care facilities, especially nursing homes. But a person doesn’t need to be sick to benefit from feline therapy. “Nothing can be quite so therapeutic as a purring kitty on your lap,” says Shojai. “My cat, Seren, seems to know when I need this sort of purr therapy. Petting her calms and reduces my stress.”

Do you need a break from everyday pressures and hassles? Hang out with your purring kitty and feel those stresses melt away.

is an award-winning pet writer and the author of Housetraining for Dummies, Senior Dogs for Dummies and Beagles for Dummies. She was honored by The Cat Writers Association as a finalist for the Muse Medallion, which recognizes excellence in writing about cats.

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Posted on July 3, 2011

Dave M says: Perhaps someone can clue me in as to why some of my cats drool all over me as I pet them? Also - why is it only some of the cats do it?
Thx. :3

Posted on January 13, 2011

Vickie says: Have 7 yo female cat. This cat has never purred. Noticed when she was about 1yo I had never heard her purr. Started to try to hear her purr and to this day have never heard her purr. My 2 others purr fine. Any ideas as to why she doesn't purr?

Posted on February 21, 2011

juanita says: we have a 17 mo. old cat named bisquit. lately he has started this habit of wanting in and soon wants out,sometimes repeating the cycle six or more times. what's up with that?

Posted on September 21, 2010

sylvia says: one morning i look out on the pourch and my other cat sweetie brough a babbie kitten on the poroch he is black but very sick i took him to my vet. she said that he was (3) months old but she weight him he was 1bl.3oz we didn't think he would make it he had very little hair on him and his eyes were running with pus in them he had fever the vet rand a lot of test on him but the only thing was he need food and loving care. well it is now one year latter skids is doing very well he is now 8bl.2oz has all his shorts and very healthly somtimes you just don't give up work with and love them cats will love you back.

Posted on November 14, 2009

Jodi says: I just gotta tell ya-- I love my cat-- I feel so important and loved when Sophie comes to me for a hug.

Posted on May 24, 2010

alan says: Eight years ago, this July, I eas doing electrical work in a huge house, sitting in the middle of 100 acres, when I heard the faint meow-ing of kittens. Being the only one in this huge house, I quietly made my way around 'til I could tell where the sounds were coming from. I realized the sounds were coming from inside a wall and then called the owner and told her I was going to cut holes in the wall to find the source. After cutting 4 holes, I found 4 kittens. I pulled them out, and carried them home. when I looked to see how they had gotten inside the wall, I found where they had fallen in through a space, in an unfinished air handler/ utility room on the second floor. I took the kittens to my vet yhe next day. After seeing them, he immediately told me they were Linx kittens. To make a long story a little shorter, three of the four were 'adopted' by his assistants, and I kept the one I call Jessie. I always considered myself a 'dog' person.I have never in my whole life had an animal that showed love to me like this cat. If at all possible, she is on me, purring constantly, and butting me with her head. I love all my animals (three dogs included). It's obvious my dogs love me, by the way they eagerly greet me when i come home or play with them, it's an obvious fact, but when Jessie's on me purring, nothing could be a greater demonstration, of the love she has, inside her, for me.

Posted on November 11, 2009

tj says: mycat is funny and crazy

Posted on November 12, 2009

marie says: Ilove my two stray siamesecats

Posted on October 23, 2009

Shawnc says: My 9 week old kitten purrs quite often. just recently it has started licking and purring. sometimes I can easily get it to stop licking and it will continue to purr. but other times it will purr right before it attacks and bites me or my 10 yearold daughter. I can not seem to get it to stop bitting, do you have any suggestions? We call her Boo because she also likes to jump out of no where and attack you (playfully).

Posted on October 22, 2009

rugger says: trying to save...2months of feeding it finally came tome puering rolling over on his back etc....took him to my vet and they didnt know how to handle it...bit a tech now is stuck there for 8 more days also have another cat at home no infected.....any chance i can save this feral fiv cat?

Posted on October 21, 2009

nancy r says: I have a large 8yr old male cat. We found a female cat a year ago that bites and jumps on the male all the time. I use a squirt bottle with water on the female, now I just show her the water bottle and she backs off.

Posted on September 28, 2009

claire bowman says: i want a cat

Posted on October 1, 2009

amanda b says: your female cat is probably a little angry about the new cat or feels threatened or something. I just brought home a 3 month old kitten and my 3 yr old female cat is insanely jealous. she kept hitting him and she's a lot bigger than her. i've been keeping the little one (davidson) in the bedroom at night alone and i do tell my female no when she hits him....she knows what im saying. when i say no she looks at me and walks away. i know that's not the best advice since you've had him for a year now but i hope that helps!

Posted on September 10, 2009

Teresa Smart says: I have five cats and all of them I have found and brought home. some of them have been abused. I have one female and four boys. My female I have had for about 4 yrs. I brought home a litte boy about 2 mons old that some one had abused. He is just the sweetest thing. My female cate from the day i brought him home has been so mean to him and is always jumping on him. He is now over a year olkd and she is still jumping on him and keeps him so scared of her. She does not miss with any of the others, just him. What can I do with her?

Posted on September 4, 2009

Barbi Dingman says: I have 2 female cats a little over a yr. old. and they are my Sweethearts. They comfort me when stressed or check on me if I'm sick they are truely 2 loving cats. I have an all white kitty & an all grey kitty & would never give them up for nothing. I lost my Mom a little over a year ago and I got my all grey cat to keep me company & then got my all white kitty to keep my all grey kitty company and they are keeping me company. they always purr when I pick them up.

Posted on August 21, 2009

Anne says: My black cat who has a tendency to bite me but not drawing blood or anything, has recently been coming on my lap. I have been diagnosed with breast cancer and believe she is now doing this because she really loves me.

Posted on August 30, 2009

John says: I had a a pure white cat growing up. Whenever you even looked at her, she would purr. She loved being in someones lap.

Posted on August 9, 2009

dawn says: my cat cries constantly and I don't know what to do, she doesn't need anything and she doesnt want to be pet she just cries and cries and its really annoying, any suggestions?

Posted on August 20, 2009

amy says: I have three male cats,ages 13yrs,5yrs,3mths i wouldn't give them up for anything, they're my pride,and joy. i love them so much they are my babies after all, so if you own a cat love it and they will love you back.

Posted on August 2, 2009

Jessica says: I have a 2yr old torbie that is like a prring machine and prres all night but,she has a scratchy and small cry.what should I do ?

Posted on August 5, 2009

Zelda Cropp says: Hi. I adopted an older cat from a friends relative to prevent her from being euthanized. I had her for almost 3 years before she would adjust to me and even though she seems more comfortable and a tad more secure, she won't let me pet her, she runs when I approach her no matter how slow my approach. She won't let me groom her and frankly it's becoming too costly for me to take her to be groomed. I have since aquired two more cats (brothers) now they are 15 months old, she adjusted to them but still won't let me approach her. Does this mean she's been abused. Ms. Bella is approximately now 8 years old. Help!

Posted on August 6, 2009

Lil says: Always had dogs & now a cat....3 yrs of being woken up at 3:30-4:00 with banging & scratching on my bedroom door..I love my cat anyway..asked everyone I knew who had a cat plus 2 vets..no one had a answer...well 2 mths ago I started feeding his dinner in spurts with the final portion just before I went to bed...WOW..he is so content now I wake up without his help after 6:00am. Was so simple to solve. Hope this helps someone else. His name is Squeeky by the way.

Posted on August 2, 2009

Renee says: I have high blood pressure problems and adopting my 2 year old cat Smudge from my local animal shelter has made my life healthier! He is my smallest best friend; and always has something to purr about. We brought each other better health and happiness!

Posted on July 19, 2009

shirley Gever says: Cat was given to me 8/10/08 and she is a wonderful cat but does not meow or purr do you think she was abused. She is a good cat and I know she loves me. Thank you

Posted on July 18, 2009

Wes Marsh says: I have a 3 yr old female calico who doesn't purr. She does however whistle through her nose. Very odd.

Posted on July 16, 2009

ken fausch says: I have a nice female young cat with a new kitter of kittens She is healthy as well as the kittens I hope. She almost never meows but all of a sudden she seems nervous and meows all the time but eats well and takes good care of her kiittens but acts like she's trying to scratch and hurt them but she doesn't.They are about 3 weeks old all active. She acts like they need to be doing something but when I take them out of the box and put them on a blanket she tries to put them back in the box and than prowls around meowing and acting like she wants to pounce on them. This is the first cat and litter we've had so I just don't know what to make of this sudden strange behavior.Should I start trying to get the kittens to eat on their own? Or just let nature take care of it Thanks

Posted on July 16, 2009

Rae says: I have found that when one of my three wonderful babies leaps onto my lap, pulls him or herself up so they are laying on my chest with their head on my neck, then start purring-- it means "Mommy, I just did something I wasn't supposed to do, and I am really, really sorry." My husband and I just couldn't do without our three babies, all of whom are rescue cats.

Posted on July 11, 2009

Lea says: I enjoyed your article very much.

Posted on July 2, 2009

Virginia K. Bryan says: Enjoyed information about purring

Posted on July 11, 2009

elizabeth vallejo says: I just want to share with everyone that I have a beautiful cat and his name is Powder. He was named because of the fact when he was born he was the only white colored one.The mama had a litter of seven,only 6 survived. Powder was the runt of the litter and the other babies wouldn't let him nurse.Well,I went to a pet store and explain what was going on.I ended up with a baby bottle and formula plus some drop for his eyes.I really didn't think he would survive,but thanks be to God,he made it!!Powder is now going on 3yrs.old!!He has brought so much love and happiness to me.My husband passed 6yrs.ago,and I surely wasn't looking or wanting a relationship with a man.So I believe God sent him to me!! My life is so busy thanks to Powder!I'm so happy and Lucky! "our babies,"pets",really are there for us.I really feel that powder feels what i go through,when and if i'm going through it. I just want to say,that because they are animals,remember that they love also.They are there for us,and can feel when we are going thru something.. Please love your Babies,they deserve it..